It's an unfortunate truth that many of the things we routinely do in our daily lives hurt the planet or other people. And we all want a certain degree of prosperity, most of us hope to have that affluence be guilt-free -- to be able to live a good life without a sense that we have become bad people -- and this can seem an insurmountable challenge when we look into the backstories of the things we buy.

But there's actually a pretty simple formula for changing a guilty lifestyle into a guilt-free (or at least less guilty) one.

First, we stop doing as many bad things as we can. (We shouldn't drive to the store when we can just as easily walk, for instance.) Second, make what we can't or won't cut out as low-harm as possible. (Most of us agree that we still need lights, but we can invest in CFLs or better monitors). Third, when we can't cut something out and can't do it in a better way, we can try and do something else that makes up for it.

That's the theory behind offsetting: balancing the harm we do by paying someone else to do something that is as good as our actions are bad.

Most readers will be familiar with the idea of carbon offsetting. This is a practice of paying a company to make investments which reduce the amount of carbon released by our society in an equal proportion to the amount we're emitting. There's all sorts of schemes for doing this -- some visionary and extremely useful, others a little less thoughtful, a few not really good at all. It's an emerging industry, and we're still learning how to design out the flaws.

But the idea of offsetting needn't stop with carbon. Earlier this year Worldchanging contributor Jer Faludi suggested a scheme for water offsets. Jer pointed out that rather than spending extravagant amounts on greywater capture systems, low-flow toilets and showers, we'd achieve greater overall water savings by financing water offsets -- buying more efficient irrigation systems for farms or orchards, which use many times more water than homes and offices. Such ideas show us both the promise of offsetting, which is to move with maximum efficiency towards a more sustainable future, and the perils associated with offsetting. The worst of those perils may be purely moral, that we being to believe that because we have the money to balance the harm we do in our lives with investments elsewhere, that the harm we do doesn't matter.

That said, at this stage of the game, and this being an imperfect world, offsets are a pretty useful thing. Here are some of the ways we've discussed them before: